Add a paragram describing how to extract line number information.

llvm-svn: 99636

1 files changed, 12 insertions, 0 deletions

diff --git a/llvm/docs/SourceLevelDebugging.html b/llvm/docs/SourceLevelDebugging.html
index 66a9a2e34ef..f92a1656a90 100644
--- a/llvm/docs/SourceLevelDebugging.html
+++ b/llvm/docs/SourceLevelDebugging.html
@@ -1069,6 +1069,18 @@ int main(int argc, char *argv[]) {
 </pre>
 </div>
 
+<p>llvm::Instruction provides easy access to metadata attached with an 
+instruction. One can extract line number information encoded in LLVM IR
+using <tt>Instruction::getMetadata()</tt> and 
+<tt>DILocation::getLineNumber()</tt>.
+<pre>
+ if (MDNode *N = I->getMetadata("dbg")) {  // Here I is an LLVM instruction
+   DILocation Loc(N);                      // DILocation is in DebugInfo.h
+   unsigned Line = Loc.getLineNumber();
+   StringRef File = Loc.getFilename();
+   StringRef Dir = Loc.getDirectory();
+ }
+</pre>
 </div>
 
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